Crane



Sept. 3, 1929. E. H. KENDALL 1,727,205

CRANE Filed Feb. 13, 1926 2 Sheets-Sheet 1 a INVENTOR yaw/1, /J-

4 fl w W640 p 3, 1929- E. H. KENDALL I 1,727,206

Patented Sept. 3,1929.

UNITED, STATES 1,727,206 PATENT. OFFICE.

EDGAR HOMER KENDALL, OF ALLIANCE, OHIO, ASSIGNOR TO THE ALLIANCE MACHINE COMPANY, OF ALLIANCE,- OHIO, A CORIORATION OF OHIO.

CRANE.

. Application filed February 13, 1926. Serial No. 88,030.

The present invention relates broadly to raising and loweringmechanism, and more particularly to cranes for this purpose embodying intergeared and separately driven drums.

It has heretofore been proposed in the art to which the present invention relates, to operate each of two permanently intergeared drums by means of separate motors, as disclosed for example, in my prior Patent 1,148,323 of July 27, 1915. Obviously, it is essential that the two drums operate at the same speed, and this requirement has presented a very considerabledifliculty, by reason of inability to insure the running of one motor at the same speed as the other, or the failure of the brakes or the motors or both to operate equally or simultaneously. If the motors should not operate synchronously,

it is apparent that there will be a tendency for the gearing of one of the drums to crawl upon the gearing of the other drum, thereby tending to raise the first drum bodily. This has frequently produced such a strain on the journals and mountings that either the mountings have been broken loose, or the journals or gearing injured.

Efforts have been made to obviate difliculties-of the nature referred to by the utilization of suitable types of slip gears as part of the driving connections of the respective motors, thereby permitting one motor to overrun the other in the event of unequal or non-simultaneous brake application. Such constructions have been extremely desirable from the standpoint of eliminating part of the difficulties previously encountered, but they have required a nonpositive driving connection which in some cases is objectionable, and the cost of the installation has been increased, without obtaining synchronism of the driving motorswith uniformity of brake application on both of the motors and drums.

The present invention has for one of its objects the provision of a crane structure in which difficulties of operation by reason of lack of synchronism or uniformity in motor or brake application are obviated by mechanically connecting the motors themselves to iI1-- sure uniformity and synchronism of the driving and controlling means for the two drums.

'In the accompanying drawings there is shown for purposes of illustration only, a preferred embodiment of my invention, it being understood that the drawings do not define the limits of my invention as changes in the constructlon and operation disclosed thereln may be made without departing from the spirit of my invention or scope of my broader claims.

In the drawings:

Figure 1 is a top plan view of one form of crane trolley embodying the present invention, and

Figure 2 is an end elevation, partly broken away, of the construction shown in Figure 1.

In carrying out the present invention there may be provided a-trolley frame'2 supported on track wheels 3- which run on tracks 4 of a traveling crane bridge.

J ournaled in suitable bearings 5 on the trolley frame, are two hoisting drums 6 placed side by side. Rigidly secured to each of the drums is a driving gear 7, these two gears directly intermeshing as clearly illustrated in the drawings. For rotating the drums there are provided motors 8 preferably located in alignment onopposite sides of the trolley frame, and having their armatures directly and mechanically connected by a common shaft 9,- herein illustrated as com-. prising the driving shaft. The motors are preferably of similar construction, and each is provided with a brake 10 which may be of the magnetic type as well understood in the art.

Adjacent each of the motors the trolley frame carries a housing 11 in each of which is journaled one end o f -.an intermediate shaft 12 extending parallel to the drums. Within the housings each of the intermediate shafts carries a worm wheel 13 both in driven relationship to worms 14 on the driving shaft 9. At their opposite ends the intermediate shafts have secured thereto gears 15 meshing with the large gears 7 on the drums. With the construction described, it will be apparent to those skilled in the art that the motors are compelled to operate in synchronism due to the direct mechanical connec-. tion between their armatures. Even in the event one motor should become defective, the other motor may drive the shaft 9, and

through it both of the drums 6 Without any ing on the respective drums, since both are acted upon uniformly' and simultaneously at all times both during drivingand brakdrums. This type of gearing not only readily provides any desired gear reduction with a powerful drive, but by properly designing the teeth can be made effective for preventing accidental orv undesired retrograde rotation of the drums. Thus, in the event of failure of both of the'motors and brakes, the crane may effectively hold its load against dropping.

I claim: I i i 1. A crane structure comprising a pair of drums each having a gear secured thereto, the drums being connected through said gears, a pinion shaft for each of the drums, said shafts aving a gear connection with the drum gears, a drive shaft, a worm gear connection between the drive shaft and each of the pinion shafts, a motor adjacent each of the worm gear connections, th'earmature of each motor being mounted on the drive shaft, and brake means for each motor.

2. A crane structure comprising a pair of drums each having a gear secured thereto, the geansmeshing with one another, a drive shaft extending substantially perpendicular to the drum shafts, a connection including worm gearing between the drive shaft and each of the drums, a driving motor adjacent each of the worm gear connections and brake means for the drive shaft adjacent each of the motors.

drums each having a gear, the gears meshing with one another, a drive shaft extending at-an angle to the drum axes, connections benection including worm gearing adjacent a motor, a gear on one drum meshing with a gear on the other drum.

5. A crane structure comprising apair of drums each having a gear, the gears meshing with one another, an intermediate shaft for each drum, each intermediate-shaft having apinion meshing with its drum gear. a worm gear on each intermediate shaft, and a common Worm shaft making a direct connection with each of said worm gears.

6. A crane structure comprising a pair of drums each having a gear, the gears meshing with one another, an intermediate shaft for each drum having a pinion meshing with the drum gear, a worm gear on each intermediate ,shaft, a shaft extending transversely of the intermediate shafts and carrying Worms meshing with the worm gears, and a driving motor adjacent each of the worm gear connections.

7. A crane structure comprising a pair of drums making a direct gear connection with one another, intermediate shafts for the drums carrying pinions whichmake a gear connection with the drums, a worm gear on each intermediate shaft, a Worm shaft extending transversely of the intermediate shafts and carryingworms meshing with the worm gears, and a driving motor adjacent v 7 each of the worm gear connections. 3. A crane structure comprising a pair of In testimony whereof I have hereunto set my hand. 

